Chemical thermometer and holder

ABSTRACT

A thermometer incorporating on a flexible and disposable substrate a plurality of spaced temperature-sensitive chemicals which are calibrated to indicate a temperature in the clinical range. The substrate is secured by a holder having a bifurcated mouthpiece and a handle extending from the mouthpiece. The bifurcated mouthpiece is generally V- or U-shaped so as to fit beneath a patient&#39;&#39;s tongue while carrying the substrate. The temperature-sensing chemicals on the substrate are activated and the holder and substrate are withdrawn for temperature reading. The substrate is disposed and a new one placed in the holder. It is a feature of the invention that there be a minimum surface area contact between the holder and the substrate to minimize heat exchange between them.

EJEW @WWS Wt 91 Brenner [11] 3 733 905 1 May 22,1973

(IHEMICAL THERMOMETER AND HOLDER inventor: Norman C. Bremer, 608 EastSeneca Street, Ithaca, N.Y. 14850 Filed: Sept. 2,1971

Appl. No.: 177,396

11.8. CI. ..73/356, 73/340, 73/358 int. Cl. "Gilli: 11/12, GOlk l/l4Field of Search ..73/340, 356, 358

References Cited UNITED STATES PATENTS Primary Examiner-Richard C.Queisser Assistant Examiner-1 rederick Shoon Attorney-Samuel J. Stoll eta1.

[ 7] ABSTRACT sensitive chemicals which are calibrated to indicate a 1temperature in the clinical range. The substrate is secured by a holderhaving a bifurcated mouthpiece and a handle extending from themouthpiece. The bifurcated mouthpiece is generally V- or U-shaped so asto fit beneath a patients tongue while carrying the substrate. Thetemperature-sensing chemicals on the substrate are activated and theholder and substrate are withdrawn for temperature reading. Thesubstrate is disposed and a new one placed in the holder. It is afeature of the invention that there be a minimum surface area contactbetween the holder and the substrate to minimize heat exchange betweenthem.

6 Claims, 7 Drawing Figures PATENTEDMAYZZIHYS INVENTOR. NORMA/V c.ERE'MER ATTORNE CHEMICAL THERMOMETER AND HOLDER REFERENCE TO RELATEDAPPLICATION This application is related to my co-pending Patentapplication Ser. No. 120,825, filed Mar. 4, 1971 and entitled BIFURCATEDTHERMOMETER PROBE.

SUMMARY OF THE INVENTION The economic realities of modern medicalpractice require that simple and repetitive tasks, however important, beperformed quickly and accurately, perhaps by unskilled personnel.Temperature measurements of patients in a large hospital may be madehundreds or thousands of times a day. Clearly, the common system ofusing breakable and hard to read glass-mercury thermometers which mustbe sterilized after each use is subject to great improvement.

The present invention makes use of recently developedtemperature-sensitive chemicals which upon reaching an ascertainedtemperature react virtually immediately by a change in a clearly visibleproperty such as color. Other such chemicals react by liquefying at apre-determined temperature. By placing a sequence of such chemicals on aflexible substrate, the sequence being temperature-sensitive at desiredintervals through a desired temperature range, it is possible to providea visible and permanent record of the temperature of the subject undertest which is clearly and accurately read by unskilled personnel. Inthecase of clinical temperature measurement the desirable range isbetween 96F and 106 F at intervals of l F. This, of course, is the rangenormally associated with the human body as measured at points whicharegenerally considered to provide accurate representations thereof, e.g.,the oral or rectal cavities.

The present invention provides a temperaturemeasuring instrument whichis capable of performing within the range and at the intervals necessaryfor clinical use while providing ease, accuracy, economyand comfort inuse together with sterility and permanence of the measured temperature.

The present invention provides a series of temperature-sensitivechemicals which change in visible property upon attaining a designtemperature. Thus, for example, a series of 100 chemical formulationscan provide temperature measurements at 1/ 10 intervals over a range of10, each formulation being adapted to change in visible property uponattaining one of the 100 temperature intervals. When serially arrangedon a substrate a scale may be provided to give visual indication of thetemperature scale employed. The substrate is exposed for temperaturemeasurement once and will thereafter retain the indicated measurementunless subsequently subjected to a higher temperature.

The present invention provides a holder for the substrate which isintended for clinical use and is adapted to be placed in the oral cavityof a patient adjacent the fraenum of the tongue. It is known to themedical profession that the most accurate measurement of bodytemperature by oral means is a measurement taken on the sides of thefraenum of the tongue and accordingly the holder is adapted to positionthe substrate in intimate contact with the underside of the tongue onthe sides of the fraenum. The holder positions the substrate in asubstantially V or U shape, covers possible sharp edges of the substrateand allows for rapid removal of used substrates and insertion of freshsubstrates. To accomplish these functions, the holder has a bifurcatedmouthpiece with arms which extend outwardly from each other in asubstantially V configuration and which join at a rounded apex. Each endof the mouthpiece has a retaining member which may be a groove and theinterior of the apex is provided with a book. The substrate, which isrelatively flexible, is placed in the mouthpiece by sliding the endsinto the mouthpiece grooves and the center into the apex book. Thesubstrate then conforms to the configuration of the bifurcatedmouthpiece and may be inserted into the oral cavity by means of a handleextending from the outside of the apex. In order to insure againstsubstantial heat transfer or loss from the substrate to the holder,provision is made to reduce the surface area contact between thesubstrate and the mouthpiece.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view of theholder of the present invention showing the bifurcated mouthpiece andthe hook and groove system for retaining the substrate.

FIG. 2 is a plan view of a substrate embodying dots ofthermally-sensitive chemical in scaled position from 96F to 106F.

FIG. 3 is a view similar to that of FIG. 1 but showing the substrate ofFIG. 2 mounted on the holder.

FIG. 4 is a side view of the holder of the present invention.

FIG. 5 is a front view of the holder of the present invention showingthe substrate mounted thereon.

FIG. 6 is a partial cross-sectional view taken across line 6--6 of FIG.5.

FIG. 7 is a fragmentary view taken across line 77 of FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION The preferredembodiment as will be described provides a semi-disposable holder for adisposable temperature-sensitive indicating plate. The notion ofdisposability is primarily an economic matter in which the cost of thedisposing of an element must be compared with the cost of retaining thatelement for repeated use. The holder of the invention may be molded froma very inexpensive plastic resin with thin wall members to bring thecost down to a minimum and make disposability after a single useeconomically practical. Conversely, the holder may be manufactured fromdurable material capable of withstanding repeated autoclaving which inlarge scale operations may be less expensive than single use holders,particularly in hospitals which already have investments in autoclavesfor glass-mercury thermometer sterilization. The preferred embodimenttakes a middle of the road approach in which the holder is adapted to berepeatedly used by one patient and then disposed and not used for anyother patient.

Referring to the drawing, the holder 10 of the present invention isprovided with the bifurcated mouthpiece 12 having a'pair of arms 14 and16 joining in a V shape at apex 18. The apex may be sufficiently roundedto provide a U shape rather than a V shape. Extending from the exteriorof the apex and preferably formed integrally with the mouthpiece is ahandle 20 including a stem 22 and a grip 24.

The outer ends of arms 14 andl6 opposite apex 18 areprovided withgrooved flanges 26 and 28 respectively formed within the V shape of themouthpiece and opening toward apex 18. The apex is provided with a hook30, and the entire bifurcated mouthpiece 12 is adapted to receive a thinflexible strip extending from grooved fiange 26 under hook 30 to groovedflange 28. The strip so secured conforms substantially to theconfiguration of the mouthpiece and may be removed simply by sliding itin the direction from whence it came, namely, in the direction of theopening of hook 30.

The temperature-indicating portion of the invention is a substrate 40bearing a series of chemicals which visibly react to particulartemperatures. Such chemicals are known in the chemical trade as surfacetemperature indicators and they react upon attaining a particular designtemperature by an immediate change in a visible characteristic. The morepopular and better known chemicals melt from a solid to a liquid uponreaching a particular temperature. Examples of such chemicals areTempil, a pellet or dot form, and Tempilaq, a solid coating form. Tempiland Tempilaq are trademarks of the Tempil Division of Big ThreeIndustrial Gas & Equipment Co., New York City. Another example isThermomelt, a trademark of Markal Company, Chicago, for liquefyingchemicals in pellet, coating, or stick form. Othertemperature-indicating chemicals change color upon attaining a designtemperature.

By arranging such temperature-indicating chemicals in a scale formationand by indexing the scale in easily readable numerals of degrees oftemperature, it is possible to determine the attained temperature of thechemicals merely by glancing at the limit of the change and the scalenumber indexed thereto. For example, in the clinical temperature rangeof 96F to 106F, assume the attained temperature is 100F. All chemicalsindicating below 100F will not have changed, yielding a continuous bandor area of change abruptly terminating at the 100F index and acontinuous band or area of no change beginning at 100F. The eyes of theobserver are quickly drawn by the bands to the interface or line betweenthe changed and unchanged portions, that location being easily read onthe marked index scale.

The formation of chemicals placed on substrate 40 will vary dependingupon manufacturing methods and chemicals employed. As shown in thedrawing the temperature-indicating chemicals are applied in a series ofdots 42, the dots being linearly arranged in correspondence with thetemperature scale. The drawing shows a double row of chemical dots butany suitable arrangement may be employed. In place of dots there may beapplied a series of parallel lines of chemicals or there may be applieda continuous but changing chemical coating.

Substrate 40 may be paper, flexible plastic or any other suitablecarrier for the chemicals. Substrate 40 may be a laminated compositionof various materials and may encapsulate the chemicals to protect themfrom environmental changes but when so encapsulated there should be atransparent overlay to allow the chemicals to remain visible.

Substrate 40 is applied to bifurcated mouthpiece 12 by sliding its edgesinto grooved flanges 26 and 28 and its central portion under hook 30 andis removed by similar sliding in the opposite direction. The holder isplaced under the tongue of the patient in intimate contact with thetissues to provide good heat transfer between the tissues andtemperature-indicating chemicals 42. If substrate 40 has an overlaycovering chemicals 42, then that overlay should be a good heat transfermedium because it is necessary for rapid temperature measurement that anequilibrium in temperature between the tissues of the mouth and thechemicals be reached quickly. There is no noticeable time lag betweenthe time the chemicals attain the measured temperature and the time theyindicate that temperature by change in visible property.

Bifurcated mouthpiece 12, if in close contact with substrate 40, wouldaffect the temperature of the substrate by heat transfer between them.This effect may be minimized by providing a plurality of small raisedbosses 32 on arms 14 and 16 inside bifurcated mouthpiece 12. This willmaterially reduce the surface area of contact between the mouthpiece andthe substrate and will correspondingly reduce heat transfer betweenthose two members.

A substrate once used should be disposed of both for hygienic reasonsand also for accuracy in temperature measurement. 7

Handle 20 may be disposed at an angle with respect to the plane ofbifurcated mouthpiece 12, this may be seen in FIGS. 3 and 6.

While the foregoing is illustrative of a preferred embodiment, it isclear that other embodiments and modifications may be had. For example,if it is desired to have an extremely low cost holder it is possible topermanently join a semi-rigid substrate 40 to a handle 20. By formingthe substrate into the bifurcated configuration necessary for goodtemperature measurement, it is possible to eliminate a separatemouthpiece. Similarly, it is possible to apply thetemperature-indicating chemicals directly to the mouthpiece, themouthpiece being the substrate.

The concept of a bifurcated mouthpiece is set forth in my co-pendingpatent application entitled Bifurcated Thermometer Probe identifiedabove. It may briefly be stated, however, that such a configurationplaces the temperature-sensing member into the pockets on opposite sidesof the fraenum of the tongue thereby securing the element againstlateral dislodgement, particularly when the mouth is open or the tongueis in motion. Careful contouring of the bifurcated mouthpiece providesfar more intimate and uniform contact with the tissues of the mouth withcorrespondingly greater accuracy of temperature measurement as comparedwith a single probe such as the common glass-mercury thermometer bulb.The substrate may be formed, for example, such that the top and bottomedges are curved back to the arms while the central part is held awayfrom the arms by bosses 32.

What is claimed is:

l. A chemical thermometer comprising:

a. a temperature-indicating means; and

b. a holder for said temperature-indicating means, said holdercomprising a bifurcated mouthpiece and a handle therefor c. saidbifurcated mouthpiece comprising a pair of arms joined at an apex tosubstantially form a V shape,

d. said bifurcated mouthpiece being provided with retaining means toremovably retain said temperature-indicating means.

2. A chemical thermometer in accordance with claim 1, wherein:

said retaining means comprises a grooved flange at the outer portion ofeach said arm and a hook within said apex.

3. A chemical thermometer in accordance with claim 1, wherein:

said arms are provided with a plurality of raised bosses to reduce the'area of surface contact between said bifurcated mouthpiece and saidtemperature-indicating means.

4. A chemical thermometer in accordance with claim 1, wherein:

said bifurcated mouthpiece is integral with, and forms at least a partof, said temperature indicating means.

5. A chemical thermometer comprising:

a. temperature-indicating means; and

b. a holder for said temperature-indicating means, said holdercomprising a bifurcated mouthpiece and a handle therefor,

bifurcated mouthpiece.

1. A chemical thermometer comprising: a. a temperature-indicating means;and b. a holder for said temperature-indicating means, said holdercomprising a bifurcated mouthpiece and a handle therefor , c. saidbifurcated mouthpiece comprising a pair of arms joined at an apex tosubstantially form a V shape, d. said bifurcated mouthpiece beingprovided with retaining means to removably retain saidtemperature-indicating means.
 2. A chemical thermometer in accordancewith claim 1, wherein: said retaining means comprises a grooved flangeat the outer portion of each said arm and a hook within said apex.
 3. Achemical thermometer in accordance with claim 1, wherein: said arms areprovided with a plurality of raised bosses to reduce the area of surfacecontact between said bifurcated mouthpiece and saidtemperature-indicating means.
 4. A chemical thermometer in accordancewith claim 1, wherein: said bifurcated mouthpiece is integral with, andforms at least a part of, said temperature indicating means.
 5. Achemical thermometer comprising: a. temperature-indicating means; and b.a holder for said temperature-indicating means, said holder comprising abifurcated mouthpiece and a handle therefor, c. saidtemperature-indicating means comprising temperature-indicating chemicalswhich change in visible property upon attaining design temperatures anda substrate for said temperature-indicating chemicals, d. saidtemperature-indicating chemicals being disposed on said substrate inscale formation, said substrate being provided with temperature indexmarkings corresponding to said scale.
 6. A chemical thermometercomprising: a. temperature-indicating means; and b. a holder for saidtemper temperature-indicating means, said holder comprising a bifurcatedmouthpiece and a handle therefor, c. said temperature-indicaTing meanscomprising temperature-indicating chemicals applied to said bifurcatedmouthpiece.